Innocent does not mean he didn't do it. You're mixing up different terms.
Besides, unless the police retroactively managed to forge a bunch of stuff online, there's a lot pointing towards him having done it.
The police have done a lot of shady shit that will hopefully free him, but the entire conspiracy that they just picked up some random guy is a bit much.
Also it's $80 fucking dollars for the base edition. Everyone complaining about Nintendo game pricing but Doom gets a pass apparently.